Donald Trump's brash campaign-trail tactics are an accidental stumble into a brash and unprecedented populist presidential bid rather than the convictions of a true believer, campaign observers say.

“I think he has stumbled on this populist campaigning style," said GOP political strategist John Feehery. "I don't think he's that ideological."

All the same, his inflammatory rhetoric has worsened existing divides among Americans.

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Trump's supporters contend the candidate is merely trying to protect us, and is willing to go further than President Barack Obama or other candidates to do so.

But Paul Achter, chairman of rhetoric and communication Studies at the University of Richmond, says the way Trump uses his words on the campaign trail represents a dramatic shift in American politics, where subtlety and inference has long reigned supreme.

“Trump’s overtly racist statements are unusual today,” Achter said in an interview. “In more recent history candidates have used coded rhetoric to raise white fears, usually with terms like ‘welfare mother,’ ‘inner-city,’ or by simply always defining blacks or other minorities as the ‘problem.’

“Racist rhetoric is usually inferential today — for example: asking, ‘Is Obama really a secret Muslim?’” Achter said. “But Trump’s rhetoric is explicitly racist. He is comparable to George Wallace, David Duke, Richard Nixon, and others who used the ‘Southern strategy’ to win office in the past.”

That strategy dates back to the 1960s, when Republican candidates tried to exploit the racial resentments of white southerners to the gains of African-Americans during the Civil Rights era.

Feehery said he believes Trump is "running as George Wallace, but would govern like Bill Clinton," meaning he would be more moderate than his language suggests should he be elected.

Trump launched his campaign with a condemnation of Latino immigrants, calling them criminals, rapists and drug dealers. And as the rhetoric has gotten only more inflammatory.

Some within his own party condemned his remarks last week calling for a ban on Muslims coming into the country, but his campaign has flourished even as he offended more ethnic and religious groups.

Josh Earnest, Obama’s chief spokesman, wasn't naming names, but it was clear he was talking about Trump when he was asked whether some campaign-trail rhetoric and policy prescriptions was fueling an uptick in racial tensions across the country.

Earnest criticized the “willingness of high-profile candidates for office in the Republican Party to use divisive, offensive rhetoric that appeals to people's fears and anxieties.”

“It doesn't make the country stronger, and it certainly is a calculated political strategy to try to divide the country to advance their campaign,” Earnest said at the daily White House briefing last week. “And it's cynical, it's repugnant, and it's something ... that the president and other people have ... spoken out against on a number of occasions.”

Though Trump’s rhetoric might be less subtle, the underlying tactic isn't new.

“Politicians do this sort of thing all the time,” said Kyle Kondik of the University of Virginia’s Center for Politics.

“The key is to find wedge issues that divide the country in ways in which the speaker is getting the bigger half of the country,” Kondik said, noting Republicans have used gay marriage and Democrats have used abortion rights to this end in the past.

“Trump may have found his own wedge issues inside the GOP on deportation and closing the country to Muslims,” Kondik noted. “What Trump has done is expanded the range of acceptable opinions for white people to express about non-white people, and expanded the range of policy options that the government should use to confront non-white people who are trying to enter the United States.”

Achter contends Trump’s rhetoric “divides his audiences into categories of ‘us’ and ‘them,’ the former being white men like himself — he hasn’t insulted women lately — and the latter being Muslims, Mexicans, terrorists and so on.”

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Statements and policy proposals such as his call to ban Muslims from entering the country confound political experts because Trump has climbed in polls as he has insulted just about every group except white males.

Indeed, Trump cracked 40 percent of Republicans and independents who lean toward the GOP this week in a Monmouth University poll .

Donald Trump Jr. told Fox News last week that his father’s rhetoric “is just resonating with people.” The front-runner’s son said when he is out in New York — which he calls “a very liberal place” — people who claim to have never voted Republican tell him: “I’m voting for your father, not because I necessarily believe he’s right, but because someone’s finally saying something.”

Sen. Jeff Sessions, an Alabama Republican who helped craft Trump’s immigration plan, says he sees no evidence of a campaign calculation to push the racial envelope. Instead, he also believes Trump’s rhetoric and policy proposals are “appealing to those who want to protect Americans.”

“Democrats have been the ones who have always accused someone who doesn’t give more to some special interest group as being uncaring and insensitive toward that group,” Sessions said. “I know who’s been dividing the country on racial lines: The Obama administration has done more in that regard than previous administrations.”